/*  sprintf(3) implementation in ActionScript 3.0.
 *
 *  Author:  Manish Jethani (manish.jethani@gmail.com)
 *  Date:    April 3, 2006
 *  Version: 0.1
 *
 *  Copyright (c) 2006 Manish Jethani
 *
 *  Permission is hereby granted, free of charge, to any person obtaining a
 *  copy of this software and associated documentation files (the "Software"),
 *  to deal in the Software without restriction, including without limitation
 *  the rights to use, copy, modify, merge, publish, distribute, sublicense,
 *  and/or sell copies of the Software, and to permit persons to whom the
 *  Software is furnished to do so, subject to the following conditions:
 *
 *  The above copyright notice and this permission notice shall be included in
 *  all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 *  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 *  DEALINGS IN THE SOFTWARE.  
 */

package {
    import com.adobe.serialization.json.*;

    /*  sprintf(3) implementation in ActionScript 3.0.
     *
     *  http://www.die.net/doc/linux/man/man3/sprintf.3.html
     *
     *  The following flags are supported: '#', '0', '-', '+'
     *
     *  Field widths are fully supported.  '*' is not supported.
     *
     *  Precision is supported except one difference from the standard: for an
     *  explicit precision of 0 and a result string of "0", the output is "0"
     *  instead of an empty string.
     *
     *  Length modifiers are not supported.
     *
     *  The following conversion specifiers are supported: 'd', 'i', 'o', 'u', 'x',
     *  'X', 'f', 'F', 'c', 's', '%'
     *
     *  Report bugs to manish.jethani@gmail.com
     */
    public function sprintf(format:String, ... args):String {
        var result:String = "";
    
        var length:int = format.length;
        for (var i:int = 0; i < length; i++) {
            var c:String = format.charAt(i);
    
            if (c == "%") {
                var pastFieldWidth:Boolean = false;
                var pastFlags:Boolean = false;
    
                var flagAlternateForm:Boolean = false;
                var flagZeroPad:Boolean = false;
                var flagLeftJustify:Boolean = false;
                var flagSpace:Boolean = false;
                var flagSign:Boolean = false;
    
                var fieldWidth:String = "";
                var precision:String = "";
    
                var next:*;
                var str:String;
    
                c = format.charAt(++i);
    
                while (c != "d"
                    && c != "i"
                    && c != "o"
                    && c != "u"
                    && c != "x"
                    && c != "X"
                    && c != "f"
                    && c != "F"
                    && c != "c"
                    && c != "s"
                    && c != "r"
                    && c != "%"
                ) {
                    if (!pastFlags) {
                        if (!flagAlternateForm && c == "#")
                            flagAlternateForm = true;
                        else if (!flagZeroPad && c == "0")
                            flagZeroPad = true;
                        else if (!flagLeftJustify && c == "-")
                            flagLeftJustify = true;
                        else if (!flagSpace && c == " ")
                            flagSpace = true;
                        else if (!flagSign && c == "+")
                            flagSign = true;
                        else
                            pastFlags = true;
                    }
    
                    if (!pastFieldWidth && c == ".") {
                        pastFlags = true;
                        pastFieldWidth = true;
    
                        c = format.charAt(++i);
                        continue;
                    }
    
                    if (pastFlags) {
                        if (!pastFieldWidth)
                            fieldWidth += c;
                        else
                            precision += c;
                    }
    
                    c = format.charAt(++i);
                }
    
                switch (c) {
                case "d":
                case "i":
                    next = args.shift();
                    str = String(Math.abs(int(next)));
    
                    if (precision != "")
                        str = leftPad(str, int(precision), "0");
    
                    if (int(next) < 0)
                        str = "-" + str;
                    else if (flagSign && int(next) >= 0)
                        str = "+" + str;
    
                    if (fieldWidth != "") {
                        if (flagLeftJustify)
                            str = rightPad(str, int(fieldWidth));
                        else if (flagZeroPad && precision == "")
                            str = leftPad(str, int(fieldWidth), "0");
                        else
                            str = leftPad(str, int(fieldWidth));
                    }
    
                    result += str;
                    break;
    
                case "o":
                    next = args.shift();
                    str = uint(next).toString(8);
    
                    if (flagAlternateForm && str != "0")
                        str = "0" + str;
    
                    if (precision != "")
                        str = leftPad(str, int(precision), "0");
    
                    if (fieldWidth != "") {
                        if (flagLeftJustify)
                            str = rightPad(str, int(fieldWidth));
                        else if (flagZeroPad && precision == "")
                            str = leftPad(str, int(fieldWidth), "0");
                        else
                            str = leftPad(str, int(fieldWidth));
                    }
    
                    result += str;
                    break;
    
                case "u":
                    next = args.shift();
                    str = uint(next).toString(10);
    
                    if (precision != "")
                        str = leftPad(str, int(precision), "0");
    
                    if (fieldWidth != "") {
                        if (flagLeftJustify)
                            str = rightPad(str, int(fieldWidth));
                        else if (flagZeroPad && precision == "")
                            str = leftPad(str, int(fieldWidth), "0");
                        else
                            str = leftPad(str, int(fieldWidth));
                    }
    
                    result += str;
                    break;
    
                case "X":
                    var capitalise:Boolean = true;
                case "x":
                    next = args.shift();
                    str = uint(next).toString(16);
    
                    if (precision != "")
                        str = leftPad(str, int(precision), "0");
    
                    var prepend:Boolean = flagAlternateForm && uint(next) != 0;
    
                    if (fieldWidth != "" && !flagLeftJustify
                            && flagZeroPad && precision == "")
                        str = leftPad(str, prepend
                                ? int(fieldWidth) - 2 : int(fieldWidth), "0");
    
                    if (prepend)
                        str = "0x" + str;
    
                    if (fieldWidth != "") {
                        if (flagLeftJustify)
                            str = rightPad(str, int(fieldWidth));
                        else
                            str = leftPad(str, int(fieldWidth));
                    }
    
                    if (capitalise)
                        str = str.toUpperCase();
    
                    result += str;
                    break;
    
                case "f":
                case "F":
                    next = args.shift();
                    str = Math.abs(Number(next)).toFixed(
                            precision != "" ?  int(precision) : 6);
    
                    if (int(next) < 0)
                        str = "-" + str;
                    else if (flagSign && int(next) >= 0)
                        str = "+" + str;
    
                    if (flagAlternateForm && str.indexOf(".") == -1)
                        str += ".";
    
                    if (fieldWidth != "") {
                        if (flagLeftJustify)
                            str = rightPad(str, int(fieldWidth));
                        else if (flagZeroPad && precision == "")
                            str = leftPad(str, int(fieldWidth), "0");
                        else
                            str = leftPad(str, int(fieldWidth));
                    }
    
                    result += str;
                    break;
    
                case "c":
                    next = args.shift();
                    str = String.fromCharCode(int(next));
    
                    if (fieldWidth != "") {
                        if (flagLeftJustify)
                            str = rightPad(str, int(fieldWidth));
                        else
                            str = leftPad(str, int(fieldWidth));
                    }
    
                    result += str;
                    break;
    
                case "s":
                    next = args.shift();
                    str = String(next);
    
                    if (precision != "")
                        str = str.substring(0, int(precision));
    
                    if (fieldWidth != "") {
                        if (flagLeftJustify)
                            str = rightPad(str, int(fieldWidth));
                        else
                            str = leftPad(str, int(fieldWidth));
                    }
    
                    result += str;
                    break;

                case 'r':
                    next = args.shift();
                    result += JSON.encode(next);
                    break;

                case "%":
                    result += "%";
                }
            } else {
                result += c;
            }
        }
    
        return result;
    }

}

// Private functions

function leftPad(source:String, targetLength:int, padChar:String = " "):String {
    if (source.length < targetLength) {
        var padding:String = "";

        while (padding.length + source.length < targetLength)
            padding += padChar;

        return padding + source;
    }

    return source;
}

function rightPad(source:String, targetLength:int, padChar:String = " "):String {
    while (source.length < targetLength)
        source += padChar;

    return source;
}

